The letters designating the identification of the interior exitstairway and ramp, such as STAIR NO. 1 or WEST STAIR, shall be placed at the top of the sign and shall be not less than 11/2 inches (38 mm) in height block lettering with 1/4-inch (6 mm) strokes.

The number designating the floor level shall be not less than 5 inches (127 mm) in height with 3/4-inch (19 mm) strokes and located in the center of the sign. The mezzanine levels shall have the letter “M” preceding the floor level. Basement levels shall have the letter “B” preceding the floor number.

Other lettering and numbers shall be not less than 1 inch (25 mm) in height.

The stairway’s upper terminus, such as ROOF ACCESS or NO ROOF ACCESS, shall be placed under the stairway identification in 1-inch-high (25 mm) block lettering with 1/4-inch (6 mm) strokes.

The lower and upper terminus of the stairway shall be placed at the bottom of the sign in 1-inch-high (25 mm) block lettering with 1/4-inch (6 mm) strokes.

Characters and their background shall have a nonglare finish. Characters shall contrast with their background, with either light characters on a dark background or dark characters on a light background.